Parasites, generally speaking, are small animals which live in or on larger animals called host. Some parasite infections are lethal. Parasites can be single-cell animals (protozoa), or multicellular animals such as helminths and arthropods. Human can acquire parasites in many ways: (1) drinking water or eating food contaminated with human excreta, (2) eating raw or inadequately cook meat or flesh of infected animals, (3) skin penetration by infective larva, (4) inhalation, (5) finger-to-mouth, and (6) bitten by insect vectors. Thailand is endemic for many parasites and food habit especially eating raw or inadequately cook meat or flesh leads to high risk of acquiring parasitic infection. Infected people may become sick and the final result is economic loss. Some important parasites are the Chinese liver fluke, pork and beef tapeworm, gnathostome, Angiostrongylus, Trichinella, etc. Knowledge about these parasites including pictures will be presented.